Did you know your body is full of simple machines? This project looks at one of the third-class levers in the human body: your arm!

Kids will enjoy this cool demonstration of Newton's Third Law and the conservation of linear momentum.

In this cool engineering science fair project, kids learn how to build Hero's engine: an enlightening example of Newton's third law.

Study the impact of environment on seed germination among three materials: soil, paper towel, and cloth. Note when seeds germinate and how well they germinate

This project examines whether humans can intuitively grasp numeric values greater than three.

Store seeds under three different environmental conditions. Plant seeds in carefully marked groups, watch them grow. Compare results.

This project compares the strength of one, two, and three-ply toilet paper.

Create homemade seed packets with your kids. This activity combines your kids' love of science and the outdoors with a little writing and drawing fun.

In this investigation, three different juices are tested to determine which juice contains the greatest amount of vitamin C.

The rock cycle will come alive for your child when he uses broken crayons to create the three basic rock types.

This science fair project idea examines the actual cost of three household light bulbs by testing energy consumption.

Examine which metal conducts more heat by boiling water in 3 pans made of aluminum, copper, and stainless steel.

In this cool project, create a lighted, scale model of the different layers of the Sun, including the core, radiation and convection zones, and photosphere.

This project explores how and how much one family can reduce the amount of garbage they accumulate over a three month period.

Make your own marshmallows and mix up some very interesting third grade chemistry lessons while you're at it!

The project compares three different methods of testing turbidity in water: the secchi disk, spectrophotometer, and turbidity test kit.

Crystals are a very special structure. In this third grade activity, your child will learn how to grow salt crystals.

Science fair project the demonstrates Newton's Third Law using a milk carton filled with water.

First grade science often covers solids, liquids, and gases. This silly science explores serious facts about the difference between all three.

How do crystals form? In this science fair project, students will use three different saturated solutions to see how different minerals form crystals over time.

This interdisciplinary card game will have your third grader working on math facts as he travels through the solar system!

Observe with your third grader what happens when food starts to decompose, and boost science skills simultaneously with this experiment!

Learn about different fern fronds with your third grader as you create lacy, natural decorations on your Easter eggs this year.

If your science savy third grader is up for a challenge, let her bend light with a casserole dish!

Test products which claim to reduce wrinkles, and determine which is the most effective. Test effectiveness over three weeks, using a sample of volunteers.

Help your fifth grader trace your family's roots and interview all the living mothers to create a makeshift, 3-D family tree!

Your third grader will be amazed at the explosive combination of vinegar and baking soda in these chocolate volcano cupcakes with white chocolate "lava."

Create a three-dimensional X-ray of your child's hand in this simple modeling activity. All you need to get started are black paper and drinking straws

Help your curious third grader construct a dazzling spinning wheel that will teach him about the science behind colors while providing some silly entertainment!

In this open-ended activity, students will be given a small quantity of three types of materials and asked to design a prototype for “something that will improve the school.”